Restricted image processing device and method for restricting usage of an image processing device

ABSTRACT

An image processing device includes a date and time information management unit for managing date and time information, a device management unit for determining, whether or not image processing is restricted based on the date and time information and based on the time of image processing, an image processing restriction unit for determining an image processing restriction when the device management unit determines that image processing is restricted, and an image processing unit for performing image processing in accordance with the image processing restriction. The restriction is a blocking of image processing or a limitation on image processing.

CROSS REFERENCE TO RELATED APPLICATION

The present application is related to, claims priority from andincorporates by reference Japanese Patent Application No. 2008-241227,filed on Sep. 19, 2008.

TECHNICAL FIELD

The present application relates to an image processing device processingan image based on inputted image data.

DESCRIPTION OF RELATED ART

In recent years, an image processing device has been connected to anetwork for transmitting and receiving image data between a server and aterminal device on the network. The image processing device can processseveral types of image data because the image processing device has amechanism for reading and scanning a manuscript, and the imageprocessing device transmits and receives a document by facsimile througha facsimile line. In such image processing devices, usability isincreased; however, since it is easy to print and send confidentialinformation, disclosure of confidential information is likely to occur.Therefore, the need for security is increased with such a device.

Japanese laid-open patent application No. 2007-260989 discloses an imageprocessing device that has a function to prevent unauthorized use ofimage data. In this reference, a level of print authorization isappended to image data; and since the level of print authorization isvaried by the time of day, unauthorized use is prevented.

However, in this reference, image data without the level of printauthorization can be easily outputted. Even if the level of printauthorization is appended to image data, if an authentication means fora device is a certain password or an IC card and those authenticationmeans are leaked to a third person, image data can be easily outputted.Therefore, a person with malicious intent may be able to acquire imagedata from a conventional image processing device without authorization.

SUMMARY OF APPLICATION

In order to resolve problems described above, the present applicationhas the following configuration.

An image processing device of the present application includes a dateand time information management unit for managing date and timeinformation, a device management unit for determining, whether or notimage processing is restricted based on the date and time informationand based on the time of image processing, an image processingrestriction unit for determining an image processing restriction whenthe device management unit determines that image processing isrestricted, and an image processing unit for performing image processingin accordance with the image processing restriction. The restriction isa blocking of image processing or a limitation on image processing.

According to the present application, since the likelihood ofunauthorized activity largely depends on the time of day, and imageprocessing functions are limited depending on the time of day,unauthorized use and misappropriation of confidential information ismore difficult. It is possible that a function enabling image processingis limited for image data that does not have a level of printauthorization.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing a structure of a multifunction machineaccording to a first embodiment.

FIG. 2 is a perspective view of a multifunction machine according to thepresent application.

FIG. 3 is a system configuration diagram including a multifunctionmachine according to the present application.

FIG. 4 is a table of image processing restriction information of amultifunction machine according to a first embodiment.

FIGS. 5A and 5B are flow diagrams showing an overall image processing ofa multifunction machine according to a first embodiment.

FIG. 6 is a block diagram showing a structure of a multifunction machineaccording to a second embodiment.

FIG. 7 is a table of date and time management information of amultifunction machine according to a second embodiment.

FIGS. 8A and 8B are a flow diagram showing an overall image processingof a multifunction machine according to a second embodiment.

FIG. 9 is a flow diagram showing date and time information updateprocesses according to a second embodiment.

DETAILED DESCRIPTION OF EMBODIMENT

An embodiment of the present application is explained below. Amultifunction machine serving as an image processing device isexplained.

[First Embodiment] FIG. 2 is a perspective view of a multifunctionmachine according to the present application. As shown in FIG. 2, themultifunction machine includes a reader unit 11, a print unit 12, anoperation panel unit 13, and a communication unit 14. The reader unit 11is a scanner using a read sensor, such as a CMOS sensor or a CCD sensor.The reader unit 11 reads a manuscript, converts the read manuscript intoan electric signal, and then converts the electric signal to image data.

The print unit 12 is, for example, an electrophotographic system. Theprint unit 12 prints image data that is read by the reader unit 11 andimage data that is received by the communication unit 14 through acommunication line and an external interface. The operation panel 13 isconfigured with operation switches, which a user manipulates to operatethe multifunction machine 10, and a display panel, which displays statusand other information relating to the multifunction machine 10 for theuser.

FIG. 3 is a system configuration diagram including the multifunctionmachine 10. As shown in FIG. 3, the multifunction machine 10 isconnected to a computer (PC) 22 and a server 23 through a LAN 20. Themultifunction machine 10 further is connected to a digital communicationnetwork 26 through a digital service unit (DSU) and a terminal adapter(TA). The multifunction machine 10 also is connected to a facsimilemachine 25 through an analog communication network 24.

The structure of the multifunction machine 10 according to the firstembodiment is explained below. FIG. 1 is a block diagram showing thestructure of the multifunction machine according to the firstembodiment. As shown in FIG. 1, the multifunction machine 10 includes adevice management unit 102, a manuscript reader unit 103, a print unit104, an image processing unit 105, an image processing restriction unit106, an operation panel unit 110, a memory unit 120, an I/F unit 130,and a date and time information management unit 140.

The device management unit 102 conducts integrated management of statusfor each unit and controls each unit with respect to each event. Thedevice management unit 102 manages to classify a time of day accordingto the present application. For example, the device management unit 102determines that 9:00 a.m. is a time of day A (discussed later), at whichpeople use devices most. The manuscript reader unit 103 is configuredwith a scanner that scans a manuscript put on a platen. The imageprocessing unit 105 converts, for example, manuscript information readby the manuscript reader unit 103 and print information received from ahost device into image data. The print unit 104 prints converted imagedata on a recording medium.

The operation panel unit 110 includes a display 111 that displays aninstruction and information for a user of the device and operationswitches 112, such as a touch panel or a key board, for inputtinginstructions and information from the user of the device.

The I/F unit 130 administers exchange of data with external devices. TheI/F unit 130 includes a facsimile communication unit 131 that conductsfacsimile communication through an analog communication network 24, anetwork communication unit 132 that conducts data communication througha LAN 20, and a local communication unit 133 that conducts datacommunication through a USB, IEEE 1284, or IEEE 1394 interface or thelike.

The image processing restriction unit 106 notifies the device managementunit 102 about an executable function of image processing based on imageprocessing restriction information 121 (discussed later) according to atime of day developed in a random access memory, or RAM, (not shown) foreach event. A date and time information management unit 140 reads dateand time management method information 123 (discussed later) anddetermines whether time correction that is entered through the operationswitches 112 by a user and time correction that is instructed throughthe I/F unit 130 by a host device are possible. When the date and timeinformation management unit 140 determines that the time correctioncorresponds to information of the date and time management methodinformation 123, the date and time information management unit 140writes the corrected time into date and time information 122.

For example, the date and time information management unit 140 acquiresthe current time from a simple network time protocol (SNTP) serverthrough a network communication unit 132 and writes the acquired currenttime into the date and time information 122.

A memory unit 120 stores a variety of information within themultifunction machine 10. For example, the memory unit 120 is anonvolatile memory, such as an electrically erasable programmableread-only memory (EEPROM). The memory unit 120 stores the imageprocessing restriction information 121 that is used by an imageprocessing restriction unit 106 to determine whether or not a functionis an executable image processing function, the date and timeinformation 122 containing a time, a day of the week, and a date (year,month, and day) that is managed by the date and time informationmanagement unit 140, and the date and time management method information123, which defines a method by which the date and time information 122can be changed, for example, manual adjustment by a user or automaticadjustment by a SNTP server. The device management unit 102 stores theinformation in the memory 120 in a RAM (not shown), and applies it inmaking decisions according to operation requests.

The date and time information 122 is constantly updated by a real timeclock (RTC) that counts time. This is done, for example, by the date andtime information management unit 140.

The following is an explanation of the image processing restrictioninformation 121, which restricts image processing jobs based on a timeof day according to the first embodiment. FIG. 4 is a table of the imageprocessing restriction information 121 of a multifunction machine 10according to the first embodiment. The table of FIG. 4 represents apredetermined set of rules governing restriction of image processing. Asshown in FIG. 4, in a column of image processing jobs, typical imageprocessing job names (such as a copy, and a print) are listed.

First, the time of day is divided into the following two categories:weekday and weekend. The weekday category is divided into fourcategories of the time of day based on the expected number of users of adevice. The division of the time of day into four categories is managedby the device management unit 102. A time of day A represents a time ofregular work hours from 8:00 to 17:59 during which the device is usedthe most. A time of day B represents a time of overtime hours from 18:00to 20:59 during which the number of users is less compared to the timeof day A. A time of day C also represents a time of overtime hours from21:00 to 23:59 in which the number of users is less compared to the timeof day B. A time of day D represents a time from 0:00 to 7:59 in whichthe least number of users are expected to use the device.

Note that a 24 hour clock is used in the times given in thisdescription. Also, the term “weekday” refers to normal business days,which are usually Monday through Friday, and the term “weekend” refersto not only Saturday and Sunday but holidays and non-business days.

The following is an explanation of the restriction of functions withrespect to the time of day for copy jobs. As shown in the table of FIG.4, copy jobs are always allowed for all functions without anyrestrictions on functions during the time of day A on weekdays. As alsoshown in FIG. 4, in the time of day B on weekdays, copy jobs are allowedin a low-resolution (for example, 200 dpi) image mode and are prevented,or blocked, in a high-resolution (for example, 600 dpi) image mode.Thus, in this case, the restriction is an imposition of a limit on imageresolution.

In the time of day C on weekdays, copy jobs are allowed in black andwhite, and color copies are prevented, as shown in FIG. 4. In the timeof day D on weekdays, copy jobs are totally prevented, as shown in FIG.4. As discussed above, copy jobs are allowed in the time of day A,however, during a time of day in which the number of users is small,color copies and high resolution copies are prevented. Therefore,unauthorized copying that may involve misappropriation of valuableinformation is more difficult.

On weekends, copy jobs are also totally prevented, or blocked.

The following is an explanation of functions with respect to the time ofday for print jobs. As shown in FIG. 4, print jobs are always allowedfor all functions without any restrictions during the time of day A onweekdays. In the time of day B on weekdays, print jobs are allowed up toa certain number of pages (for example, up to 100 pages), and areprevented for jobs over a certain number of pages (for example, over 100pages).

In the time of day C on weekdays, print jobs are restricted in the samemanner as copy jobs except that there is a limit on the number of pagesprinted during time of day B on weekdays. In the time of day D onweekdays and on weekends, print jobs are totally prevented.

As discussed above, print jobs are allowed without any restrictions offunctions in the time of day A, however, during a time of day in whichthe number of users is small, there is a limit on the number of pagesthat can be printed. Therefore, unauthorized taking of confidentialinformation is more difficult.

The following is an explanation of restrictions on functions withrespect to the time of day for scan to e-mail jobs. As shown in FIG. 4,scan to e-mail jobs are always allowed for all functions without anyrestrictions during the time of day A on weekdays. In the time of day Bon weekdays, scan to e-mail jobs are allowed up to a certain file sizeof scanned data (for example, up to 5 MB) and are restricted for filesizes over the certain file size of scanned data (for example, over 5MB).

In the time of day C on weekdays, scan to e-mail jobs are allowed forblack and white data up to a certain file size (for example, 2 MB), andcolor data is prevented. In the time of day D on weekdays and weekends,scan to email jobs are totally prevented.

As discussed above, scan to email jobs are allowed without anyrestrictions of functions in the time of day A, however, during a timeof day in which the number of users is small, there are restrictionsconcerning file size and color. Therefore, with these restrictions,unauthorized taking of confidential information is more difficult.

The following is an explanation of restrictions of jobs that involvescanning to a folder of a storage device. As shown in FIG. 4, scan tofolder jobs are always allowed for all functions without anyrestrictions on functions during the time of day A on weekdays. In thetime of day B on weekdays, scan to folder jobs are allowed to a computer(PC) or a server connected to an intranet, or local area network, of acompany and are prevented if the folder is on a PC or a server connectedto a network outside the company, as shown in FIG. 4.

In the time of day C on weekdays, scan to folder jobs are allowed forscanned black and white data to a folder on a PC or a server connectedto an intranet of the company and are prevented for color data, as shownin FIG. 4. In the time of day D on weekdays and weekends, scan to folderjobs are totally prevented, as shown in FIG. 4.

As discussed above, scan to folder jobs are allowed for without anyrestrictions of functions in the time of day A, however, during a timeof day in which the number of users is small, there are restrictions ondestination and color data. Therefore, with these restrictions,unauthorized taking of confidential information is more difficult.

The following is an explanation of restrictions on functions withrespect to the time of day for scan to portable memory jobs. Portablememory refers to portable drives or miniature memory cards that use thecommon USB interface or another standard PC interface. As shown in FIG.4, scan to portable memory jobs are always allowed for all functionswithout any restrictions on functions during the time of day A onweekdays. In the time of day B on weekdays, scan to portable memory jobsare allowed when the scanned resolution is equal to or less than 200 dpiand are prevented when the scanned resolution is over 200 dpi, as shownin FIG. 4.

In the times of day C and D on weekdays, scan to portable memory jobsare totally prevented, as shown in FIG. 4. With respect to a removablememory, such as a portable memory, that is easily carried, since outputto portable memory is restricted entirely during much of the day,unauthorized taking of confidential information is more difficult.

On weekends and non-business days, such as holidays, restrictions onscan to portable memory jobs are the same as those of the time of day D.However, for example, scan to portable memory may be allowed in acertain period of the day on weekends, so that users who work onweekends have access to this function.

The following is an explanation of the restrictions on PC scan jobs. Ascan to folder job, as discussed above, is controlled and managed by themultifunction machine itself. In contrast, a PC scan job is controlledand managed by a PC connected to an intranet of a company. In otherwords, the scanner function of the multifunction machine is controlledand managed by the PC. The scanned data under a PC scan job is typicallystored in a local hard drive of the PC. As shown in FIG. 4, PC scan jobsare always allowed for all functions without any restrictions onfunctions during the time of day A on weekdays. In the time of day B onweekdays, PC scan jobs are allowed up to a certain number of pages (forexample, up to 50 pages), and are prevented over the certain number ofpages (for example, over 50 pages).

In the time of day C on weekdays, PC scan jobs are allowed in a blackand white data with the same or more strict scanning page numberrestrictions as the time of day B. Further, PC scan jobs using colordata are prevented. In the time of day D on weekdays and on weekends, PCscan jobs are totally prevented.

As discussed above, PC scan jobs are allowed without any restrictions offunctions in the time of day A, however, during a time of day in whichthe number of users is small, there are limits on the number of scannedpages an on color scanning. With these restrictions, unauthorized takingof confidential information is more difficult.

The following is an explanation of restrictions with respect to the timeof day for facsimile transmission jobs. As shown in FIG. 4, facsimiletransmission jobs are always allowed for all functions without anyrestrictions on functions during the time of day A on weekdays. In thetime of day B on weekdays, facsimile transmission jobs are allowed up toa certain number of pages (for example, up to 20 pages) and arerestricted for scans over a certain number of pages (for example, over20 pages).

In the time of day C on weekdays, facsimile transmission jobs areallowed in a black and white or in a regular (lower) color resolutionwith the same or more strict page number restrictions as the time of dayB. Further, facsimile transmission of data in color or with extra-fineor photo resolutions is prevented in time of day C. In the time of day Don weekdays and on weekends, facsimile transmission jobs are totallyprevented.

As discussed above, facsimile transmission jobs are allowed without anyrestrictions of functions in the time of day A, however, during a timeof day in which the number of users is small, there are limits on thetransmission page number, and high-resolution and color facsimiletransmissions are prevented. Therefore, with these restrictions,unauthorized taking of confidential information is more difficult.

Finally, facsimile reception jobs are triggered by another device.Therefore, during all times of day on weekdays and on weekends,facsimile reception jobs are allowed without any restrictions.

The following is an overall explanation of the multifunction machine 10.FIGS. 5A and 5B are flow diagrams showing image processing of amultifunction machine according to the first embodiment. Operation ofthe multifunction machine 10 according to the first embodiment isexplained below in the order of steps S101 through S118 with referenceto FIG. 1.

(S101) The multifunction machine 10 receives an image processing requestby a user through operation switches 112 or an I/F unit 130.

(S102) When a device management unit 102 receives an image processingrequest, the device management unit 102 reads data and time information122 stored in the memory unit 120 through the date and time informationmanagement unit 140 to determine whether or not it is a time of day toconduct an image processing restriction.

(S103) The device management unit 102 decides whether or not therestriction of image processing is required based on the read date andtime information 122. When the current time of day is such that it isrequired to conduct an image processing restriction, i.e., the currenttime is within any of the time of day B, C, and D on weekdays and onweekends, the operation goes to S104. When the time of day is such thatit is not required to restrict image processing, i.e., the current timeis within the time of day A, the operation goes to S108.

(S104) Since the read date and time information 122 is within one of thetimes of day B, C, and D on weekdays and on weekends that requirerestrictions, the device management unit 102 instructs the imageprocessing restriction unit 106 to confirm whether or not it is applyingthe image processing restriction. When f the image processingrestriction is being applied, the operation goes to S106. When the imageprocessing restriction is not being applied, the operation goes to S105.

(S105) At this step, even though the current date and time information122 is in one of the times of day B, C, and D on weekdays and onweekends in which an image processing restriction should be applied, theimage processing restriction is not actually applied, so the devicemanagement unit 102 instructs the image processing restriction unit 106to set the image processing restriction.

(S106) The device management unit 102 reads the day of the week and timefrom the date and time information 122 to determine the current time inimposing an image processing restriction. In particular, the devicemanagement unit 102 determines whether or not the current time of day iswithin a weekend or one of times C and D on a weekday. When the currenttime of day is within the time of day B on a weekday, the operation goesto S110. When the time of day falls in a weekend or in times of day Cand D on a weekday, the operation goes to S107.

(S107) When the current date and time information 122 is within one ofthe times of day C and D on a weekday or is within a weekend, the devicemanagement information 102 switches the image processing restrictioninformation 121 to other image processing restriction information 121that corresponds to the date and time information 122.

(S108) In step S103, when the device management unit 102 determines thatthe time of day is such that an image processing restriction is notrequired, i.e., the current time is within the time of day A on aweekday, the device management unit 102 instructs the image processingrestriction unit 106 to confirm whether or not an image processingrestriction is being applied. When an image processing restriction isbeing applied, the operation goes to S109. When no image processingrestriction is being applied, the operation goes to S110.

(S109) In this step, even though the current date and time information122 is in the time of day A on a weekday, in which no image processingrestriction should be applied, an image processing restriction isactually being applied, so the device management unit 102 instructs theimage processing restriction unit 106 to release the image processingrestriction.

(S110) The device management unit 102 determines whether or not an imageprocessing restriction is required, according to the time of day, on therequested image processing. When the current time of day is in the timeof day A on a weekday, in which no image processing restriction isrequired, the operation goes to S111. When the current time of day iswithin a weekend or in the times of day B, C, and D on a weekday, theoperation goes to S112.

(S111) When the current time of day is in the time of day A, in which norestriction is required, the device management unit 102 executes therequested image processing.

(S112) When the current time of day is within a weekend or in the timesof day B, C, and D on a weekday, in which image processing restrictionis required, the device management unit 102 instructs the imageprocessing restriction unit 106 to confirm whether the requested imageprocessing function is entirely prevented. The image processingrestriction unit 106 determines whether the requested function isprevented or limited based on image processing restriction information121. When the requested function is entirely prevented, or blocked, theoperation goes to S113. When the requested function is not prevented butis limited, the operation goes to S115.

(S113) When the requested function is entirely prevented, the devicemanagement unit 102 instructs the display of message indicating that therequested image processing function is prohibited at the display 111 fornotifying the user.

(S114) Then, the device management unit 102 cancels image processing,destroys image data for the requested image processing, and waits for anext operation request.

(S115) When there is an image processing restriction, or limit, withrespect to the requested image processing function, the devicemanagement unit 102 instructs that the image processing restriction(s)be displayed at the display 111 for notifying the user.

(S116) After the user recognizes the image processing restrictionthrough the display 111, the user inputs either an indication ofagreement with the restriction or cancellation of the requested imageprocessing through the operation switches 112.

(S117) The device management unit 102 divides an operation based on theuser's input of either agreement with the restriction or cancellation ofthe requested image processing. When the user agrees to the imageprocessing restriction, the operation goes to S118. When the usercancels the requested image processing, the operation goes to S114.

(S118) Upon the user's agreement to the image processing restriction,the device management unit 102 instructs an image processing unit 105 toexecute the requested image processing in consideration of the imageprocessing restriction, and finishes the operation.

According to the first embodiment discussed above, since the degree oflikelihood of unauthorized use of a multifunction machine relateslargely to the time of day, and enablement of image processing islimited depending on the time of day, unauthorized use of themultifunction machine is more difficult. In the multifunction machine,it is possible that unauthorized use is restricted for image data thatdoes not have a level of print authorization.

[Second Embodiment] In a second embodiment, the time used fordetermining the time of day in a multifunction machine cannot be changedby a person with malicious intent, so that taking of confidentialinformation is more difficult. FIG. 6 is a block diagram showing aconfiguration of a multifunction machine according to the secondembodiment. As shown in FIG. 6, a multifunction machine 20 is configuredwith a device management unit 102, a manuscript reader unit 103, a printunit 104, an image processing unit 105, an image processing restrictionunit 106, an operation panel unit 110, a memory unit 220, an I/F unit130, and a date and time information management unit 240.

Parts that are different from the first embodiment are explained indetail below. Elements that are the same as corresponding elements ofthe first embodiment have the same reference numeral and are notexplained to avoid redundancy.

The memory unit 220 stores a variety of information within themultifunction machine 20. For example, the memory unit 220 is anonvolatile memory, such as an EEPROM. The memory unit 220 stores imageprocessing restriction information 121, which is used by an imageprocessing restriction unit 106 to determine whether a function is anexecutable image processing function, date and time information 122containing a time, a day of the week, and a date (year, month, and day),which is managed by a date and time information management unit 240, anddate and time management method information 223, which defines a methodby which the date and time information 122 can be adjusted, for example,manual adjustment by a user or automatic adjustment by an SNTP server.In the second embodiment, when an image processing restriction isapplied, the date and time information 122 can be changed only by theautomatic adjustment method. Therefore, changing the time by a personwith malicious intent is prevented, which makes it more difficult tocircumvent the restrictions the machine.

The date and time information management unit 240 reads the date andtime management information 223, and determines whether time correctionthat is entered through the operation switches 112 by a user and timecorrection that is instructed through the I/F unit 130 by a host deviceare possible. When the time correction is possible, the date and timeinformation 122 is changed with the corrected time. As discussed above,when an image processing restriction is applied, the date and timeinformation management unit 240 corrects the time only by the automaticadjustment method.

In the first embodiment, the date and time information management unit140 acquires the current time from an SNTP server through a networkcommunication unit 132 and writes the acquired current time into thedate and time information 122. In addition to that, the date and timeinformation management unit 240 can acquire the current time through,for example, a network time protocol (NTP) server, a radio-controlledclock, or a GPS clock, and can write the acquired current time into thedate and time information 122.

The following is an explanation of date and time management information223 according to the second embodiment. FIG. 7 is a table of the dateand time management information 223 of a multifunction machine 20according to the second embodiment. As shown in FIG. 7, in a column ofdate and time management information items that are managed by the dateand time information management unit 240, there are management method,ability to change the management method, ability to manually change thedate and time information, source for acquisition in an automaticoperation, and time interval for acquisition in automatic operation.

As shown in FIG. 7, a column of operation status is generally dividedinto regular operation and operation under an image processingrestriction. Regular operation represents a status in which an imageprocessing restriction is not applied, i.e., a time of day A (8:00a.m.-17:59 p.m. on weekdays) as shown in the first embodiment. Inregular operation, there are two management methods, manual managementand automatic management. In manual management, a certain user inputsthe time through operation switches 112. In automatic management, thetime is set by a host device through an I/F unit 130. The operationunder an image processing restriction occurs when the current time ofday is within one of the times of day B, C, and D (18:00 p.m.-7:59 a.m.on weekdays) and any time on weekends, during which restrictions areapplied, as discussed in the first embodiment.

In the regular operation, the management under the column of the dateand time management information items is divided into manual managementand automatic management. Under manual management, a user of themultifunction machine 20 corrects the time through the operationswitches 112 to amend the date and time information 122. Under automaticmanagement, the time is periodically acquired from an SNTP serverthrough the I/F unit 130 and the date and time information 122 iscorrected based on the acquired time. Automatic management is usuallychosen in operations under an image processing restriction of the secondembodiment. Therefore, a person with malicious intent cannot change thecurrent time in the machine, which makes it difficult to circumvent therestrictions on the machine.

Next, the row denoted with ability to change the status of themanagement under the column of the date and time management informationitems indicates whether a user is permitted to change between manualmanagement and automatic management. In regular operation, a request bya user to change between manual management and automatic management isallowed. However, when operating under an image processing restriction,a request by a user to change between manual management and automaticmanagement is not allowed.

The row denoted by ability to rewrite date and time information underthe column of the date and time management information items indicateswhether correction of the date and time information 122 by a user of themultifunction machine 20 through the operation switches 112 is allowed.Under automatic management, manual correction of the date and timeinformation 122 is not allowed.

The source for acquisition of the current time in an automatic operationis an SNTP server, as shown in FIG. 7. A time interval of acquisition inan automatic operation is ten minutes in the regular operation, and oneminute under an image processing restriction, as shown in FIG. 7. Whenthe time interval is shorter, more accurate date and time management ispossible.

The following is an explanation of overall image processing with themultifunction machine 20 according to the second embodiment. FIGS. 8Aand 8B form an overall flow diagram showing image processing of themultifunction machine 20 according to the second embodiment. Severalsteps are added after steps S105 and S109 compared with the flow diagramof FIGS. 5A and 5B of the first embodiment. Therefore, an operation ofthe multifunction machine 20 according to the second embodiment isexplained below with respect to added steps S210 through S204 withreference to FIGS. 6, 8A and 8B.

(S201) When a device management unit 102 instructs an image processingrestriction unit 106 to apply an image processing restriction in S105,the device management unit 102 instructs the date and time informationmanagement unit 240 to change the operation status to automaticmanagement in the date and time management information 223.

(S202) Then, the device management unit 102 instructs the date and timeinformation management unit 240 to acquire the current time from a SNTPserver through an I/F unit 130 and to correct the date and timeinformation 122.

(S203) When the device management unit 102 instructs the imageprocessing restriction unit 106 to release an image processingrestriction in S109, the device management unit 102 instructs the dateand time information management unit 240 to return the date and timemanagement information 223 to regular operation status.

(S204) The device management unit 102 instructs the date and timeinformation management unit 240 to determine whether or not to correctthe date and time information 122 by management method based on the dateand time management information 223 under regular operation status. Inother words, when the management method is automatic management, thedate and time information 122 is corrected by acquiring the current timefrom the SNTP server through the I/F unit 130. When the managementmethod is manual management, the date and time information is correctedas to the time inputted by the user of the multifunction machine 20through operation switches 112.

The following is an operation flow of date and time information updateprocesses according to the second embodiment. FIG. 9 is a flow diagramshowing date and time information update processes according to thesecond embodiment. An operation flow of the date and time informationupdate processes according to the second embodiment is explained belowin the order of steps S250 through S254.

(S250) A device management unit 102 instructs a date and timeinformation management unit 240 to confirm whether a management methodis manual management or automatic management for date and timemanagement method information 223. When the management method isautomatic management, the operation goes to S251. When the managementmethod is manual management, the operation goes to S254.

(S251) When the management method is automatic management, the devicemanagement unit 102 instructs the date and time information managementunit 240 to acquire the current time from a SNTP server, which isdesignated as the source of acquisition of the current time, through anI/F unit 130.

(S252) The date and time information management unit 240 corrects thedate and time information 122 based on the acquired current time.

(S253) The device management unit 102 instructs the date and timeinformation management unit 240 to notify a time interval foracquisition of the current time stored in date and time managementmethod information 223 to the device management unit 102 with respect tothe automatic management status. The device management unit 102instructs a timer (not shown) to count time for the interval to acquirethe current time from the SNTP server in a continual manner.

(S254) When the management method is manual management, the date andtime information is corrected based on the time inputted by the user ofthe multifunction machine 20 through operation switches 112, and then anoperation is finished.

As discussed above, according to the second embodiment, it is difficultfor a person with malicious intent to change the time used fordetermining the current time of day in the multifunction machine, sothat it is difficult to circumvent the restrictions on the machine.

In the first and second embodiments, a multifunction machine is given asan exemplary application of an image processing device. However, in viewof the effect of the present application, the security features of thisapplication can be applied to an image forming device, a copier, afacsimile machine, a printer, a scanner and the like.

1. An image processing device, comprising: a date and time informationmanagement unit for managing date and time information; a devicemanagement unit for determining, whether or not image processing isrestricted based on the date and time information and based on the timeof image processing; an image processing restriction unit fordetermining an image processing restriction when the device managementunit determines that image processing is restricted; and an imageprocessing unit for performing image processing in accordance with theimage processing restriction, wherein the restriction is a blocking ofimage processing or a limitation on image processing.
 2. The imageprocessing device according to claim 1, wherein the image data istransmitted to an external device.
 3. The image processing deviceaccording to claim 2, wherein the external device is one of a facsimilemachine, a computer, a server, and a memory device.
 4. The imageprocessing device according to claim 3, wherein the memory device iseither a USB memory device or a memory card.
 5. The image processingdevice according to claim 1, wherein the device management unitdetermines whether image processing is prevented according to a currenttime of day.
 6. The image processing device according to claim 1,wherein the image processing restriction unit determines a type of therestriction from among a plurality of restriction types based on acurrent time of day.
 7. The image processing device according to claim6, wherein the restriction types include prevention of high resolutionimage processing and imposition of a limit on pages of images that areprocessed.
 8. The image processing device according to claim 1, whereinthe date and time information management unit acquires current date andtime information from one of a radio-controlled clock, a GPS clock, anetwork time protocol (NTP) server, and a simple network time protocol(SNTP) server.
 9. The image processing device according to claim 1,wherein the date and time information management unit prevents manualchanges of the date and time information during predetermined times. 10.A method of image processing with an image processing machine including:reading current date and time information from a source of date and timeinformation; determining, based on the current date and timeinformation, whether image processing should be restricted, based on apredetermined set of rules; if it is determined that image processingshould be restricted, determining a type of restriction to be imposed onthe machine based on the predetermined set of rules; and restrictingimage processing according to the type of restriction to be imposed, ifit is determined that image processing should be restricted.
 11. Themethod of image processing according to claim 10, wherein therestricting of image processing includes limiting the resolution ofimages to relatively low resolutions during predetermined times.
 12. Themethod of image processing according to claim 10, wherein therestricting of image processing includes limiting a number of pages ofimages that can be processed to a predetermined value duringpredetermined times.
 13. The method of image processing according toclaim 10, wherein the restricting of image processing includes limitingimage processing to black and white images during predetermined times14. The method of image processing according to claim 10, wherein themethod includes restricting image processing during a time when a numberof potential users of the machine is likely to be relatively low basedon the current time of day information.
 15. The method of imageprocessing according to claim 10, wherein the method includes preventinga user from manually changing the date and time information on themachine.